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Q:

# A watch which gains uniformly is 2 minutes low at noon on monday and is 4 min.48 sec fast at 2 p.m on the following monday. when was it correct ?

 A) 2 p.m on Tuesday B) 2 p.m on Wednesday C) 3 p.m on Thursday D) 1 p.m on Friday

Answer:   B) 2 p.m on Wednesday

Explanation:

Time from 12 p.m on monday to 2 p.m on the following monday = 7 days 2 hours = 170 hours

$\therefore$ The watch gains $\inline&space;\left&space;(&space;2+4\frac{4}{5}&space;\right&space;)$ min. or  $\inline&space;\frac{34}{5}$ min. in 170 hrs.

Now, $\inline&space;\frac{34}{5}$ min. are gained in 170 hrs.

$\inline&space;\therefore$ 2 min are gained in $\inline&space;\left&space;(&space;170\times&space;\frac{5}{34}\times&space;2&space;\right&space;)$ hrs = 50 hrs

$\inline&space;\therefore$ Watch is correct 2 days 2 hrs. after 12 p.m on monday i.e it will be correct at  2 p.m on wednesday.

Q:

How many minutes does a watch lose per day, if its hands coincide every 64 minutes ?

 A) 36 7/9 min B) 32 8/11 min C) 34 3/11 min D) 65 5/11 min

Explanation:

55 min. spaces are covered in 60 min.

60 min. spaces are covered in min. = min.

Loss in 64 min. = min.

Loss in 24 hrs = min. = min.

3 97
Q:

How many degrees will the minute hand move, in the same time in which the second hand move 4800 ?

 A) 80 deg B) 160 deg C) 140 deg D) 135 deg

Explanation:

As minute hand covers, 60 degrees

Minute hand covers 4800/60 = 80°

1 106
Q:

At what time, between 3 o’clock and 4 o’clock, both the hour hand and minute hand coincide each other  ?

 A) 3:16 7/11 B) 3:16 11/4 C) 3:30 D) 3:16 4/11

Explanation:

Coincide means 00  angle.

This can be calculated using the formulafor time A to B means  [11m/2 - 30 (A)]

Here m gives minutes after A the both hands coincides.

Here A = 3, B = 4

0 =11m/2 –30 × 3
11m = 90 × 2 = 180
m= 180/11 = 16 4/11

So time = 3 : 16 4/11

1 54
Q:

A watch gains 5 seconds in 3 minutes and was set right at 8 AM. What time will it show at 10 PM on the same day ?

 A) 10 : 27 : 41 AM B) 8 : 51 : 04 AM C) 9 : 45 : 15 PM D) 10 : 23 : 20 PM

Explanation:

The watch gains 5 seconds in 3 minutes = 100 seconds in 1 hour.

From 8 AM to 10 PM on the same day, time passed is 14 hours.

In 14 hours, the watch would have gained 1400 seconds or 23 minutes 20 seconds.

So, when the correct time is 10 PM, the watch would show 10 : 23 : 20 PM

4 248
Q:

How many degrees will the minute hand move, in the same time in which the second hand move 5400 ?

 A) 90 degrees B) 85 degrees C) 60 degrees D) 45 degrees